I read an interesting article in View Camera about using 4x5 Graphic with Graflok Back (preferred Crown) as a 120 panoramic camera. The article suggested using a Shen-Hao 6x12 back (they also make a 6x17 back for 4x5). The web page showing 6x12 is: http://www.badgergraphic.com/search_product2.asp?x=3375

Do you know anyone who has actually used these backs and do you have any suggestions.

My reply may sound a little biased, but to each his own, I guess. There are a few things that have never made sense to me. One is the use of a 120 roll film back on a 4X5 camera. When I take a 4X5 out to shoot, it's because I want 4X5 negatives. Second, I can't for the life of me understand why anyone would pay the kind of money that those 6X12 holders cost just to get the same result you can get by shooting loose and cropping 4X5 film. There's nothing "panoramic" about them and cropping 4X5 gives you much more room to compose the print in the darkroom. I suppose if one really wanted to get "panoramic", one could shoot 5 inch long strips of 35mm film. The fact remains, you still get the same thing you get with a 35mm strip from the middle of a 4X5 sheet. Nothing more, nothing less.

While I agree with Glenn about the use of RF backs (in traditional formats like 6X7 or 2X3)on 4X5 cameras, I think the 6X12 backs have a place and I recently bought a Horseman. While it is true that you can "shoot loose" and crop to fit with a 4X5 negative, I find that having a dedicated back makes more sense for me. It also is more economical to operate, especially using the outdated 120 roll film I am fond of. Go ahead and laugh, but it's a buck a roll and I have never had any problems.

One big problem (at least for me) with the 6X17 format is that you cannot use a conventional 4x5 enlarger for it. Otherwise, the format is strongly panoramic, which is not really something you can say about the 6X12 which is borderline.

I suspect that the comments in the View Camera article were on target regarding the merits of the different backs; none of them are cheap. You may want to try Glenn's idea first to see if you like the "format". But in order to try to make yourself think in terms of 6X12, make a finder mask for your tube finder so you can get a better idea as to what you are capturing.

There are a few manufacturers of these chinese backs. One is Kang Tai, and another is Da Yi, and I think it may be the Da Yi backs that are being sold through Shen Hao, but it's possible that they are making their own as well. There are a few slightly different variations, mainly involving the viewing system and the way the masks are installed for different formats.

I have the Da Yi 6x17 back and have posted a bit about it on apug.org and the forum at lfphoto.info.

It's neat to be able to get a wider format than 4x5" on a 4x5" camera. These 617 backs work like an extension back, so you focus with a groundglass viewer that has as much extension as the back.

Unlike a 617 back on a 5x7" camera, though, you're restricted to a lens range of about 75mm to 150mm due to mechanical vignetting at the long end and the inherent extension in the back at the short end. You can use longer lenses, but you won't get the full 6x17 frame--still 6x15 with a 300mm lens isn't bad, and for a pano format, a range of 75-150mm isn't so bad either.

The build quality might be described as "industrial," but it's quite a functional solution, and for the $550 or so that I paid, cheaper than any other 6x17 option out there. It uses a film window counter system, so it's mechanically simple--not much to go wrong.

For 6x12 and 6x9 there are masks that go inside the back and counter windows for different formats. Some of the newer ones place the masks outside the back, so that you can swap formats mid-roll.

I don't have a 5x7" enlarger, so I don't think I'll be enlarging these conventionally (occasionally maybe in a friend's darkroom or rented darkroom space). I'll probably make some contact prints on Azo, and I might scan the color ones for Chromira prints.

Thank you all for your input which covers just about the whole spectrum. First, I should preface my remarks with the fact that I am new at taking large format pictures (have considerable experience dealing with large format negatives - have done some work on historical photographs).

Glenn, I agree with you that a 6x9 back belongs on a 6x9 camera for most applications.

I share in many regards disemjg's approach. I like the size, particularly the width of a 4x5 and find dealing potentially with roll film more friendly than sheet film for many reasons.

David, thank you for your post and references to other postings. I found them very valuable and have ordered via ebay source the 6x17 back. 6x12 originally was to be a learning step, but decided to go ahead with larger back which adds an additional dimension to the project.

The other equipment I will be using for the project for your information will be Graflex View, Crown and Speed cameras (I have collected a large number of Graflex products and find them fasinating to say the least.) - all work at this time in black and white. The negatives will be scanned on my Microtek i900 (can do up to 8x10 at 3200dpi) and printed on my Epson 2200 (can go up to 13x44 inch prints) with new software to give better reproduction of black and white. While results may be several months away, I will post here reference to my photographic web site when I have something interesting.

Thank you all for your help with this last piece of the equipment puzzle. John